1. Field of the Invention
The present invention relates to an image-forming apparatus, and more particularly, to an image-forming apparatus that is equipped with a recording head for ejecting ink droplets and a transport belt for transporting sheets of recording media.
2. Discussion of the Background
As an image-forming apparatus, such as a printer, a facsimile machine, a plotter, or a multifunction machine including at least two of these functions, a liquid-ejecting image-forming apparatus such as an inkjet recording device that uses a recording head for ejecting ink droplets is known. It is to be noted that imaging, recording, and printing are synonymous with “image forming” in the descriptions below.
There are two types of the liquid-ejecting image-forming apparatus. A serial type image-forming apparatus forms images using a recording head that ejects ink droplets while moving in a main scanning direction. A line type image-forming apparatus forms images using a recording head that remains stationary while ejecting ink droplets.
In either case, the liquid-ejecting image-forming apparatus forms images by ejecting the ink droplets from the recording head onto a sheet while the sheet is being transported. Therefore, transport characteristics of the image-forming apparatus profoundly affect imaging performance.
One known liquid-ejecting image-forming apparatus is equipped with a transport unit that transports sheets while sucking air so as to draw the sheets to a transport belt using a suction fan disposed inside the transport belt.
Another known liquid-ejecting image-forming apparatus includes a transport unit to transport sheets using a transport belt, an image-recording unit such as a recording head that is equipped with several ink-ejecting ports aligned in the same direction as a direction in which the transport unit transports the sheets, and a release mechanism that switches the transport unit between an image-recording state and a release state to facilitate removal of jammed sheets. In the image-recording state, the transport unit can transport the sheets closes to the ink ejecting ports. In the release state, the transport unit is disengaged from all ink releasing ports and is almost parallel to or inclined with respect to the image-recording unit.
Another known liquid-ejecting image-forming apparatus includes a recording medium detector disposed in a transport path of the recording medium. When the recording medium detector detects jamming of the recording medium, the image-forming apparatus stops a transport unit that transports the recording medium, and determines whether or not jammed sheets can be automatically discharged. When the image-forming apparatus determines that the sheets can be automatically discharged, the image-forming apparatus automatically discharges, the recording medium to outside.
However, in an image-forming apparatus that transports sheets while suctionally attracting the sheets to the transport belt using a suction fan, a nozzle of the recording head might be damaged by contact with the sheets if the suction fan is stopped-immediately in case of a paper jam, because a force attracting the sheets to the surface of the transport belt then disappears.
Additionally, simply moving the transport belt to the releasing position distant from the recording head leaves the sheets on the transport belt, which must then be removed manually.